Method and apparatus for managing disc defects

ABSTRACT

A defect management method and apparatus including (a) recording data in predetermined units of data; (b) verifying the recorded data to detect an area of the disc in which a defect exists; (c) designating an area from the defective area to the following area containing data as the defective area or designating only the defective area as the defective area; (d) recording information regarding the designated defective area as temporary defect information in a data area of the disc; and (e) recording information, which is used to manage the temporary defect information, in a temporary defect management information area. The method and apparatus are applicable to write once discs and suitable for recording different types of data, thereby enabling more appropriate real-time data reproduction.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of International Application No.PCT/KR2003/001878, filed on Sep. 9, 2003 which is based on KoreanApplication No. 2002-54755, filed Sep. 10, 2002 in the KoreanIntellectual Property Office, the disclosures of which are incorporatedherein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to disc defect management, and, moreparticularly, to a method of managing a defect in a disc in a mannerregarding different types of data and an apparatus to manage a defect ina disc.

2. Description of the Related Art

Defect management refers to a process of rewriting the data stored in auser data area of a disc in which a defect exists. The data is rewrittento the data area of the disc to compensate the data loss caused by thedefect. In general, defect management is performed using linearreplacement or slipping replacement. In linear replacement, the userdata area in which a defect exists is replaced with a spare data areahaving no defects. In slipping replacement, the user data area with thedefect is slipped and the next user data area having no defects is used.

Both linear replacement and slipping replacement are applicable only todiscs, such as a DVD-RAM/RW, on which data is repeatedly recorded andrecording is performed using a random access method. In other words,linear replacement and slipping replacement are difficult to apply towrite once discs on which recording is allowed only once. In general,the presence of defects in a disc is detected by recording data on thedisc and confirming whether or not data has been recorded correctly onthe disc. However, once data is recorded on a write once disc,overwriting new data and managing defects therein is impossible.

After the development of CD-R and DVD-R, a high-density write once discwith a recording capacity of several dozen GBs was introduced. This typeof disc may be used as a backup disc, since this type of disc is notexpensive and allows random access so as to enable fast readingoperations. However, defect management is not available for write oncediscs. Therefore, a backup operation is discontinued when a defectivearea, i.e., an area where a defect exists, is detected during the backupoperation because defect management on a write once disc is notperformed. In general, a backup operation is performed when a system isnot frequently used, e.g., at night when a system manager does notoperate the system.

However, the recording of user data that is recorded from a defectivearea of the data area to the data area so as to enable defect managementis not always a satisfactory solution. For real-time reproduction ofdata, appropriately reading data on time is important. In general,audio/video (AV) data requires reproduction in real time since thereproduction of AV data is perceived by the visual and auditory sensesof a human being during the reproduction. Human visual and auditorysenses are more sensitive to an error in real-time reproduction of AVdata than an error in reproduction of specific AV data content caused bya trivial defect contained in the AV data. In fact, human ears may beincapable of detecting an error when audio data is incompletelyreproduced. As specified previously, when an area of a disc isdesignated as a defective area, slipping replacement may be used torewrite data to a following area. That is, when an area of a disc isdesignated as a defective area, the following area where data isrecorded is also considered to be unavailable and is determined to be adefective area, and the data recorded in the defective area isrewritten. In this case, the defective area is skipped and data is readfrom the next area during reproduction of the data. However, skippingthe defective area causes a delay in reading data from the disc, and thedelay in reading makes reproduction of the data in real-time difficult.As is described above, human ears are more sensitive to an error causedby a failure of real-time reproduction than an error caused byincomplete reproduction of AV data. Unlike AV data, reproducing,editing, or searching for control data may be relatively very difficultwhen even a small amount of the control data is lost.

SUMMARY OF THE INVENTION

The present invention provides a defect management method and apparatusthat manage a defect occurring in a disc in a manner suitable to recorddifferent types of data so as to improve reproduction characteristics.

The present invention also provides a defect management method andapparatus that are applicable to a write once disc and manage a defectoccurring in that disc in a manner suitable to record different types ofdata, thereby improving reproduction characteristics.

According to an aspect of the present invention, there is provided amethod of managing defects in a disc, comprising: (a) recording data inpredetermined units of data; (b) verifying the recorded data to detectan area of the disc in which a defect exists; (c) designating an areafrom the defective area to the following area containing data as adefective area or designating only the defective area as the defectivearea; (d) recording information regarding the designated defective areaas temporary defect information in a data area of the disc; and (e)recording information, which is used to manage the temporary defectinformation, in a temporary defect management information area.

According to an aspect of the invention, the method further includes (f)repeating operations (a) through (e) before finalizing of the disc,wherein previously recorded information is recorded with the temporarydefect information during the (d) operation; and (g) recordinginformation, which is most recently recorded in the temporary defectinformation area and the temporary defect management information area ina defect management area during the finalizing of the disc.

According to an aspect of the invention, during the (c) operation, thearea from the defective area to the following area containing data isdesignated as the defective area, or only the defective area isdesignated as the defective area, depending on the type of the recordeddata. Also, according to a further aspect of the invention, during the(c) operation, only the defective area is designated as the defectivearea when the recorded data is AV data, and the area from the defectivearea to the following area containing data is designated as thedefective area when the recorded data is control data.

According to another aspect of the present invention, there is provideda method of managing defects in a disc, comprising: (a) recording datain predetermined units of data; (b) verifying the recorded data todetect an area of the disc in which a defect exists; (c) designating anarea from the defective area to the following area containing data as adefective area, or designating only the defective area as the defectivearea; (d) storing information regarding the designated defective area asfirst temporary defect information in memory; (e) repeating operations(a) through (d) before a recording operation is expected to end; (f)reading the temporary defect information from the memory and recordingthe temporary defect information in a temporary defect information areaof the data area so as to correspond to the recording operation, whenthe recording operation is expected to end; and (g) recordinginformation, which is used to manage the information recorded in thetemporary defect information area in the (f) operation, in a temporarydefect management information area.

According to an aspect of the invention, during the (f) operation,information to designate the temporary defect information area isfurther recorded in the temporary defect information area.

According to an aspect of the invention, the method further includes (h)repeating operations (a) through (f) before finalizing of the disc,wherein previously recorded information is recorded with the temporarydefect information during the (f) operation in the temporary defectinformation area; and (i) recording information, which is most recentlyrecorded in the temporary defect information area and the temporarydefect management information area, in a defect management area.

According to an aspect of the invention, during the (c) operation, thearea from the defective area to the following area containing data isdesignated as the defective area, or only the defective area isdesignated as the defective area, depending on the type of the recordeddata. According to a further aspect of the invention, during the (c)operation, only the area having the defect is designated as thedefective area when the recorded data is AV data, and the area from thedefective area to the following area containing data is designated asthe defective area when the recorded data is control data.

According to yet another aspect of the present invention, there isprovided a recording apparatus comprising a recording/reading unit thatrecords data on or reads data from a disc; and a controller thatverifies the data recorded on the disc using the recording/reading unitso as to detect an area of the disc in which a defect exists, designatesan area from the defective area to the following area containing data asa defective area or designates only the defective area as the defectivearea, creates information regarding the designated defective area,provides the created information to the recording/reading unit, controlsthe recording/reading unit to record the created information astemporary defect information in a data area of the disc, createsmanagement information to manage the temporary defect information,provides the management information to the recording/reading unit, andcontrols the recording/reading unit to record the management informationin a temporary defect management area.

According to an aspect of the invention, the controller controls therecording/reading unit to further record the previously recordedinformation with the information, and controls the recording/readingunit to record information, which is most recently recorded in thetemporary defect information area and the temporary defect managementinformation area in a defect management area during finalizing of thedisc. According to another aspect of the invention, the controllerdesignates the area from the defective area to the following areacontaining data as the defective area, or designates only the defectivearea as the defective area, depending on the type of the recorded data.According to a further aspect of the invention, the controllerdesignates only the defective area as the defective area when therecorded data is AV data, and designates the area from the area to thefollowing area containing data as the defective area when the recordeddata is control data.

According to still another aspect of the present invention, there isprovided a recording apparatus comprising memory; a recording/readingunit that records data on a disc in predetermined units of data andreads the recorded data from the disc; and a controller that verifiesthe data recorded on the disc using the recording/reading unit so as todefect an area of the disc in which a defect exists; designates the areafrom the defective area to the following area containing data as thedefective area or designates only the defefctive area as the defectivearea; stores information regarding the designated defective area asfirst temporary defect information in the memory; repeats the verifyingof the data, the designating of the defective area, and the storing ofinformation regarding the designated defective area before a recordingoperation is expected to end; reads the temporary defect informationfrom the memory when the recording operation is expected to end;provides the read temporary defect information to the recording/readingunit; controls the recording/reading unit to record the temporary defectinformation in a temporary defect information area of the data area in amanner corresponding to the recording operation; creates managementinformation to manage the temporary defect information area; providesthe management information to the recording/reading unit; and controlsthe recording/reading unit to record the management information in atemporary defect management information area.

According to an aspect of the invention, the controller createsinformation for the temporary defect information area, provides thecreated information to the recording/reading unit, and controls therecording/reading unit to further record the created information in thetemporary defect information area. According to another aspect of theinvention, the controller controls the recording/reading unit to furtherrecord the previously recorded information with the information; readsinformation, which is most recently recorded in the temporary defectinformation area and the temporary defect management information area,during the finalizing of the disc; and controls the recording/readingunit to record the most recently recorded information in the defectmanagement area again. According to yet another aspect of the invention,the controller designates the area from the defective area to thefollowing area containing data as the defective area or designates onlythe defective area as the defective area, depending on the type of therecorded data. According to a further aspect of the invention, thecontroller designates only the defective area as the defective area whenthe recorded data is AV data, and designates the area from the defectivearea to the following area containing data as the defective area whenthe recorded data is control data.

Additional and/or other aspects and advantages of the invention will beset forth in part in the description which follows and, in part, will beobvious from the description, or may be learned by practice of theinvention.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects and advantages of the invention will becomeapparent and more readily appreciated from the following description ofthe embodiments, taken in conjunction with the accompanying drawings ofwhich:

FIG. 1 is a block diagram of a recording apparatus according to apreferred embodiment of the present invention;

FIG. 2A illustrates a structure of a single record layer disc accordingto a preferred embodiment of the present invention;

FIG. 2B illustrates a structure of a double record layer disc accordingto a preferred embodiment of the present invention;

FIG. 3 illustrates details of the structures of the discs shown in FIGS.2A and 2B;

FIG. 4 is a diagram illustrating a process in which temporary defectinformation is created and recorded, according to a preferred embodimentof the present invention;

FIG. 5 illustrates data structures of temporary defect informationaccording to a preferred embodiment of the present invention;

FIG. 6 illustrates data structures of information regarding defect #iand information regarding temporary defect information #i, which arerecorded in a temporary defect information area;

FIG. 7 is a flowchart illustrating a defect management method accordingto a preferred embodiment of the present invention; and

FIG. 8 is a flowchart illustrating a defect management method accordingto another preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Reference will now be made in detail to the present embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings, wherein like reference numerals refer to the like elementsthroughout. The embodiments are described below in order to explain thepresent invention by referring to the figures.

FIG. 1 is a block diagram of a recording apparatus according to anembodiment of the present invention. Referring to FIG. 1, the recordingapparatus includes a recording/reading unit 1, a controller 2, and amemory 3. The recording/reading unit 1 records data on a disc 100 (e.g.,an information storage medium according to an embodiment of the presentinvention), and reads back the data from the disc 100 to verify theaccuracy of the recorded data. The controller 2 performs defectmanagement according to the present invention. In this embodiment, thecontroller 2 uses a verify-after-write method in which the accuracy ofdata is verified after the data is recorded in predetermined units. Morespecifically, the controller 2 causes the recording/reading unit 1 torecord user data on the disc 100 in predetermined units, and verifiesthe accuracy of the user data so as to detect defects in the user data.

If a defect is detected, the controller 2 creates defect informationthat indicates the position of a defective area on the disc 100. If anarea containing a defect is detected, the controller 2 designates onlythe specific area as a defective area, designates a set of areas fromthe specific area to the following area containing data, and/orcompletes a combination of the designation of only the specific area asa defective area and the designation of a set of areas from the specificarea to the following area containing data. Every time defectinformation is created, the controller 2 stores the defect informationin the memory 3. When the amount of stored defect information reaches apredetermined level, the stored defect information is recorded astemporary defect information on the disc 100. Also, the controller 2records management information, which is used to manage the recordedtemporary defect information, as temporary defect management informationon the disc 100.

In this embodiment, recording temporary defect information and temporarydefect management information on the disc 100 is periodically performedper recording operation. A recording operation is a unit of work that isdetermined according to either an intention of a user or is a recordingwork to be performed. According to this embodiment of the invention, arecording operation indicates a process in which the disc 100 is loadedinto the recording apparatus, data is recorded on the disc 100, and thedisc 100 is taken out from the recording apparatus. During the recordingoperation, data is recorded and verified at least once; in general,though, data is actually verified several times. When a user presses theeject button (not shown) of the recording apparatus in order to removethe disc 100 after the recording of data, the controller 2 expects therecording operation to be terminated. Next, the controller 2 createstemporary defect information and temporary defect managementinformation, and provides the created temporary defect information andthe created temporary defect management information to therecording/reading unit 1 to be recorded on the disc 100. The temporarydefect information, which is obtained as a result of the recording andverifying by the controller 2, is stored in the memory 3.

If the recording of data on the disc 100 is completed, i.e., no moredata will be recorded on the disc 100 (i.e., the disc 100 is to befinalized), the controller 2 records the temporary defect informationand the temporary defect management information in a defect managementarea (DMA) of the disc 100.

FIGS. 2A and 2B illustrate structures of a disc according to anembodiment of the present invention. FIG. 2A illustrates, in detail, arepresentation of a single recording layer of disc 100 having arecording layer L0′. The disc 100 includes a lead-in area, a data area,and a lead-out area as shown. The lead-in area is located in an innerpart of the disc 100 in a radial direction and the lead-out area islocated in an outer part of the disc 100 in a radial direction. The dataarea is located between the lead-in area and the lead-out area, and isdivided into a user data area and a spare area. The user data area is anarea where user data is recorded. The spare area is the substitute areafor a user data area having a defect, serving to compensate for loss inthe recording area due to a defect. On the assumption that defects mayoccur within the disc 100, in an embodiment of the invention, the sparearea assumes 5% of the entire data capacity of the disc 100, so that agreater amount of data may be recorded on the disc 100. Also, in anembodiment of the invention, the spare area is provided at an end of thedata area of the disc 100. In the case of a write once disc, the sparearea must be located at the end of the data area of the disc. Thisallows slipping replacement to be performed while the spare area data isrecorded, starting from the inner part toward the outer part of the disc100.

According to this embodiment, the spare area is present only between theuser data area and the lead-out area. If necessary, a portion of theuser data area may be used as another spare area, that is, more than onespare area may be present between the user data area and the lead-outarea.

FIG. 2B illustrates a representation of a double recording layer of disc100 having two recording layers L0 and L1. A lead-in area, a data area,and an outer area are sequentially formed from an inner part of thefirst recording layer L0 in a radial direction to an outer part thereof.Also, an outer area, a data area, and a lead-out area are sequentiallyformed from an outer part of the second recording layer L1 in a radialdirection to an inner part thereof. Unlike the single recording layerL0′ shown in FIG. 2A, the lead-out area is present in the inner part ofthe disc 100 of FIG. 2B. That is, the disc 100 of FIG. 2B has anopposite track path (OTP) in which data is recorded starting from thelead-in area of the first recording layer L0 toward the outer area andcontinuing from the outer area of the second recording layer L1 to thelead-out area.

FIG. 3 illustrates details of the structures of the embodiments of thedisc 100 shown in FIGS. 2A and 2B. Referring to FIG. 3, a discmanagement area (DMA) is present at least once in the lead-in area, thelead-out area, or the outer area of the disc 100. Also, a temporarydefect management area is formed at least once in the lead-in area orthe lead-out area. A temporary defect information area is formed in thedata area according to a recording operation.

In general, information which relates to managing defects in the disc100 is recorded in the DMA. Such information includes the structure ofthe disc 100 that allows the disc 100 to manage defects, the position ofdefect information, whether defect management is performed or not, andthe position and size of a spare area. In the case of a write once disc,new data is recorded after previously recorded data when the previouslyrecorded data changes. In general, when a disc is loaded into arecording/reproducing apparatus, the apparatus reads data from a lead-inarea and a lead-out area of the disc to determine how to manage thedisc, and records data on or reads data from the disc. However, if theamount of data recorded in the lead-in area increases, a longer time isspent on preparing the recording or reproducing of data after loadingthe disc. Accordingly, the present invention proposes the use oftemporary defect management information and temporary defectinformation. That is, only the temporary defect management information,which is comparatively more important than the temporary defectinformation, is recorded in the lead-in area. The temporary defectinformation is recorded in the data area. In an embodiment of theinvention, new information is added to the previously recordedinformation in the temporary defect information area so that allrecorded information is accumulated therein. The recording/reproducingapparatus reads the most recently recorded temporary defect information.The recording/reproducing apparatus then detects defects throughout thedisc based on the result of the reading of the most recently recordedtemporary defect information. Thus, information regarding the locationof the most recently recorded temporary defect information is recordedin the temporary defect management information area where the temporarydefect management information is recorded.

More specifically, information regarding a defect that occurred in arecording unit #1 and information regarding a defect that occurred in arecording unit #2 are recorded in a temporary defect information area #1and a temporary defect information area #2, respectively. Defectmanagement information to manage the temporary defect information areas#1, #2, . . . and #n is recorded in the temporary defect managementinformation area. If additional data cannot be recorded on the disc 100or a user does not wish to record any more data on the disc 100, i.e.,the disc 100 needs to be finalized. In a finalization operation of thedisc 100, the temporary defect information recorded in the temporarydefect information area and the temporary defect management informationrecorded in the temporary defect management information area are allrecorded in the DMA.

The reason to record the temporary defect management information and thetemporary defect information in the DMA again will now be explained.Where additional data will not be recorded on the disc 100, i.e., thedisc 100 needs to be finalized, the temporary defect managementinformation, which is updated several times, and the temporary defectinformation, which is recorded in the data area, are rewritten to theDMA of the lead-in area so as to enable the relatively fast reading ofinformation recorded on the disc 100. Also, increasing the reliabilityof information by recording the defect management information in aplurality of areas is possible.

In this embodiment, defect information recorded in the temporary defectinformation areas #0 through #i-1 is recorded repeatedly in a temporarydefect information area #i. Therefore, reading the defect informationfrom the last temporary defect information area and recording thisinformation in the DMA again during the finalizing of the disc 100 issufficient.

FIG. 4 is a diagram illustrating a process in which temporary defectinformation is created and recorded. With reference to FIG. 4, a unit ofdata may be processed in units of sectors or clusters. A sector denotesa minimum unit of data that is managed in a file system of a computer orin an application, and a cluster denotes a minimum unit of data that maybe physically recorded on a disc at once. In general, one or moresectors constitute a cluster.

There are two types of sectors: a physical sector and a logical sector.The physical sector is an area on a disc where a sector of data is to berecorded. An address to detect the physical sector is called a physicalsector number (PSN). The logical sector is a unit to manage data in afile system or in an application. An address to detect the logicalsector is called a logical sector number (LSN). A discrecording/reproducing apparatus detects the recording position of datausing a PSN and, when recording data on a disc, substantially all of thedata is managed in units of LSNs in a computer or in an application. Therelationship between an LSN and a PSN is changed by a controller of therecording/reproducing apparatus, based on whether the disc contains adefect and an initial position of recording data.

Referring to FIG. 4, A denotes a data area in which PSNs are allocatedto a plurality of sectors (not shown) in ascending order. In general,each LSN corresponds to at least one PSN. However, since LSNs areallocated to non-defective sectors in ascending order, thecorrespondence between the PSNs and the LSNs is not maintained when adisc has a defective area, even if the size of a physical sector is thesame as that of a logical sector.

Sections {circle around (1)} through {circle around (5)} denote units ofdata in which verifying work is performed after recording work. Indetail, a recording apparatus records user data in section {circlearound (1)}, returns to the start of section {circle around (1)}, andchecks if the user data is appropriately recorded or if a defect existsin section {circle around (1)}. If a defect is detected, only the areacovering the defect in section {circle around (1)} is designated as adefective area. Here, the defect is designated as defect #1. Next, therecording apparatus records the user data in section {circle around(2)}, returns to the start of section {circle around (2)}, and checks ifthe user data is appropriately recorded or if a defect exists in thestart. If a defect is detected, only the area covering the defect insection {circle around (2)} is designated as a defective area and thedefect is designated as defect #2. Likewise, defect #3 is determinedwith respect to section {circle around (3)}. However, in the case ofsection {circle around (3)}, the defective area is designated asextending to an end of the area containing the defect. Since a defect isnot detected in section {circle around (4)}, a defective area is notdetermined in section {circle around (4)}.

Temporary defect information #1 is recorded when recording operation #1is expected to end, and after the recording and verifying of data in thesection {circle around (4)}, i.e., when a user presses the eject buttonof a recording apparatus or recording of user data allocated in arecording operation is completed. Temporary defect information #1contains information regarding defects #1 through #3 occurring insections {circle around (1)} through {circle around (4)}. Only an areacontaining a defect is determined to be a defective area in section{circle around (4)}, and an area from the area containing a defect tothe following area containing data is determined to be the defectivearea in sections {circle around (5)} and {circle around (6)}. Similarly,temporary defect information #2 is recorded according to recordingoperation #2. Temporary defect information #1 also contains informationregarding an area part in which user data is recorded according torecording operation #1, the part having a defect and thus beingdesignated as a defective area. Also, temporary defect information #2contains information regarding an area part in which the user data isrecorded according to recording operation #2, the part having a defectand thus being designated as another defective area. Also, temporarydefect information #2 further contains the information contained intemporary defect information #1.

When a defect is detected from an area of disc 100, data recording maybe performed in one of two methods. In the first method, only thespecified area is designated as a defective area, data recorded in thedefective area is not rewritten, and data recording is continued afterthe defective area. In the second method, data recorded in the defectivearea, which includes an area from the area containing the defect to thefollowing area containing data and which is designated a defective area,is rewritten. That is, the defective data is restored using slippingreplacement, and then, the data recording is continued. Selection of oneof the first and second methods is determined depending on the type ofdata to be recorded. For instance, if the data to be recorded is AV datathat needs to be reproduced in real time, the first method is selected.That is, only the area containing the defect is designated as adefective area and data recorded in the defective area is not rewritten.In contrast, if the data to be recorded is control data, such asnavigation data that is used to reproduce, search for, or edit the AVdata, the second method is selected. In data reproduction, the degree oferror due to control data loss is greater than that which is due to AVdata loss.

According to embodiments of the invention, a reason to choose to rewritedata recorded in a defective area, based on data characteristics willnow be described. In general, AV data needs to be reproduced in realtime because AV data is perceived by human ears when AV data isreproduced. Human visual and auditory senses are more sensitive to anerror in real-time reproduction of AV data than to an error inreproduction of specific AV data content caused by a trivial defectcontained in the AV data. In fact, human ears are substantiallyincapable of detecting an error when audio data is incompletelyreproduced. As specified previously, when an area of a disc isdesignated as a defective area, slipping replacement may be used torewrite data to a following area. That is, when an area of a disc isdesignated as a defective area, the following area where data isrecorded is also considered as unavailable and determined to be adefective area, and the data recorded in the defective area isrewritten. In this case, the defective area is skipped and data is readfrom the next area during reproduction of the data. However, skippingthe defective area causes a delay in reading data from the disc, and thedelay in reading makes reproduction of data in real-time difficult. Asis described above, human ears are more sensitive to an error caused bya failure of real-time reproduction than an error caused by incompletereproduction of AV data. In general, a disc drive included in areproducing apparatus has various types of error correction functionssuch as error correction code (ECC). Thus, the disc drive may be capableof restoring at least a portion of data that cannot be appropriatelyread during the reproduction operation. For this reason, when a defectexists in an area of a disc during AV data recording, only the specifiedarea is designated as the defective area and data recorded in thedefective area is not rewritten in another area.

It is noted that a case exists where AV data is reproduced in real timebut does not need to be recorded in real time. The case includes storingAV data in an auxiliary storage device, such as a hard disc drive (HDD),and recording the stored AV data on the disc 100. That is, AV data maybe recorded using an editing tool to be used with AV data. Inparticular, AV data that does not need to be recorded in real time maybe easily recorded according to the present invention.

In contrast, if only a portion of control data is lost, reproducing,editing, and searching for the control data may be difficult. Thus, if adefect exists in an area of a disc during the recording of control data,both the area having the defect and the following area containing datais designated as a defective area and data recorded in the defectivearea is rewritten in another area.

The diagram of FIG. 4 illustrates data recording. More specifically, thediagram of FIG. 4 illustrates a first recording operation on a discwhere a defect exists, using one of two methods. In the first method,only the area having the defect is designated as a defective area anddata recording is continued after the defective area without rewritingdata previously recorded in the defective area. In the second method, adefective area is designated to include the area having the defect andthe following area containing data. Following the designations the datapreviously recorded in the defective area is rewritten. However, thepresent invention is not limited to this description. That is, discdefects may be processed according to other methods besides the firstand second methods, depending on a format of recorded data.

FIGS. 5A and 5B illustrate data structures of temporary defectinformation according to embodiments of the present invention. Referringto FIG. 5A, temporary defect information #1 contains informationregarding defect #1, defect #2, and defect #3. The information regardingdefect #1 discloses the position of defect #1 as recorded in the disc,the information regarding defect #2 discloses the position of defect #2as recorded in the disc, and the information regarding defect #3discloses the position of defect #3 as recorded in the disc.

Temporary defect information #1 also includes the information regardingdefect #1, the information regarding defect #2, the informationregarding defect #3, and the information regarding temporary defectinformation #1. The information regarding temporary defect information#1 indicates the position of temporary defect information #1. Readingthe information recorded in temporary defect information #1 duringreproduction of user data is not required since the user data is notrecorded in temporary defect information #1. That is, for thereproduction of the user data, distinguishing between defective area #iand temporary defect information #1 is meaningless. Therefore, temporarydefect information #1 contains position information and thus may beuseful in that the information may be used to indicate that the userdata is not recorded in temporary defect information #1 during thereproduction of the user data.

Referring to FIG. 5B, temporary defect information #2 includes all ofthe information contained in temporary defect information #1 and furthercontains information regarding defects #4, #5, and #6, in addition tothe information recorded in temporary defect information #2. Temporarydefect information #2 also contains information regarding the positionof temporary defect information #1.

FIGS. 6A and 6B illustrate data structures of information regardingdefect #i recorded in a temporary defect information area, andinformation regarding temporary defect information #i. Referring to FIG.6A, the information regarding defect #i includes first stateinformation, second state information, starting and ending points, and areserved area of defect #i. State information is flag information thatindicates whether the present area is a defective area in which a defectexists or is a temporary defect information area in which temporarydefect information is recorded. In this embodiment, the first stateinformation is included in the information regarding defect #i and thusmust be understood as flag information indicating that the present areais a defective area. The second state information is flag informationthat indicates one of two options. The first option declares that onlythe area having the defect is designated as the defective area and thatdata recording is continued after the defective area without anyrewriting of the data previously recorded in the defective area. Thesecond option declares that an area from the area having the defect tothe following area containing data is designated as a defective area.Following the designation the data recorded in the defective area isrewritten. In the case of defect area #1 shown in FIG. 4, which includesonly the area having the defect, the second state information disclosesdesignation of a defective area covering defect area #1 and datarecorded in defect area #1 as not rewritten. The information regardingthe starting point represents the start of the present area, i.e., thestart of the defect #i. The information regarding the ending pointrepresents the end of the present area, i.e., the end of the defect #i.The reserved area is referred to as an area that is reserved forrecording other information.

Referring to FIG. 6B, the information regarding temporary defectinformation #i also includes first state information, second stateinformation, starting and ending points, and a reserved area oftemporary defect information #i. State information is flag informationthat indicates whether the present area is a defective area in which adefect exists or is an area in which temporary defect information isrecorded. The first state information included in the informationregarding temporary defect information #i is flag information indicatingthat a present area is an area in which temporary defect information isrecorded, rather than an area in which a defect exists. The inclusion ofthe second state information into the information regarding temporarydefect information #i is optional. The second state information is flaginformation indicating the same as that which is described for theinformation regarding defect #i. If the verify-after-write method isalso performed on data recorded in a temporary defect information areaand the data is rewritten when a defect exists in the temporary defectinformation area, the second state information is flag informationindicating the rewriting of the data.

Hereinafter, a defect management method according to the presentinvention will be described.

FIG. 7 is a flowchart illustrating a defect management method accordingto an embodiment of the present invention. Referring to FIG. 7, inoperation 701, a recording apparatus records defect information,regarding data recorded according to a first recording operation, asfirst temporary defect information in a data area of a disc. Thisprocess serves to manage defects in the disc. In operation 702, therecording apparatus records defect management information, which is usedto manage the first temporary defect information, as first temporarydefect management information in a temporary defect managementinformation area in at least one of a lead-in area and a lead-out areaof the disc. In operation 703, the recording apparatus records the firsttemporary defect information and defect information, regarding datarecorded according to a second recording operation, as second temporarydefect information in the data area. In operation 704, the recordingapparatus records defect management information, which is used to managethe second temporary defect information, as second temporary defectmanagement information in the temporary defect management informationarea. In operation 705, whether the disc needs to be finalized ischecked. In operation 706, if the disc does not need to be finalizedaccording to the result of operation 705, operations 701 through 704 arerepeated while indexes, which are given to the recording operations, thetemporary defect information, and the temporary defect managementinformation, are increased. In an embodiment of the invention, thisincrease is by a value of 1. During the finalizing of the disc, the mostrecent defect management information and temporary defect information,which are recorded until operation 704, are recorded in a DMA inoperation 707. That is, the most recently recorded temporary defectmanagement information and temporary defect information are recorded asthe final temporary defect management information and temporary defectinformation in the DMA. In operation 707, the final temporary defectinformation and defect management information may be recorded repeatedlyin the DMA to increase the reliability of data detection. Further, theverify-after-write method may be performed on the final temporary defectmanagement information and temporary defect information. If a defect isdetected from this information, the area of the disc in which the defectexists and data recorded after the area with the defect may be regardedas unavailable, i.e., they are designated as a defective area, and thefinal temporary defect management information and temporary defectinformation may be recorded again after the defective area.

FIG. 8 is a flowchart illustrating a defect management method accordingto another embodiment of the present invention. Referring to FIG. 8, arecording apparatus records user data on a data area of a disc inpredetermined units of data to facilitate the verify-after-write method,in operation 801. In operation 802, the data recorded in operation 801is verified to detect the existence of detects in any area of the dataarea where a defect exists. In operation 803, whether data recorded inthe area having the defect will be rewritten is determined. As mentionedabove, the rewriting of data is determined in consideration of thecharacteristics of data to be recorded. In one option, only the areawith a defect is designated as the defective area and data recorded inthe defective area is not rewritten. In the other option, both the areawith the defect and the following area containing data are designated asthe defective area and data recorded in the defective area is rewritten.

If the data recorded in the area having the defect will not be rewrittenaccording to the result of operation 803, defect information is createdin operation 804 and used to designate only the area having the defectas the defective area. In contrast, if the data recorded in the areahaving the defect will be rewritten according to the result of operation803, defect information is created in operation 805, and used todesignate the area from the area having the defect to the following areacontaining data as the defective area. In operation 806, the defectinformation created in operation 804 or operation 805 is stored as firsttemporary defect information. In operation 807, whether a recordingoperation is expected to end is checked. If the recording operation isnot likely to end according to the determination of operation 807,operations 801 through 806 are repeated before the end of the recordingoperation.

If the recording operation is likely to end, i.e., the recording of theuser data is complete by user input or according to the recordingoperation, according to the determination in operation 807, the firsttemporary defect information is read and recorded in temporary defectinformation area #1 of the data area, in operation 808. In operation809, information designating temporary defect information area #1 as adefective area is further recorded in first temporary defect informationarea #1. In operation 810, first temporary defect management information#1, which is used to manage temporary defect information #1, is recordedin a temporary defect management information area. In operation 811,whether the disc needs to be finalized is checked. If the disc is not tobe finalized according to the result of operation 11, operations 801through 810 are repeated before the finalizing. In operation 812,indexes, which are given to the temporary defect information, thetemporary defect information area, and the temporary defect managementinformation, are increased whenever operations 801 through 810 arerepeated. According to an embodiment of the invention, the increase isby a value of 1. If the disc needs to be finalized, according todetermination in operation 811, the most recently recorded temporarydefect information #i and temporary defect management information #i arerecorded as the final temporary defect information and temporary defectmanagement information in a DMA in operation 813. The final defectinformation and defect management information may be recorded repeatedlyin the DMA several times so as to increase the reliability of datadetection. Further, the verify-after-write method may be performed onthe final temporary defect management information and temporary defectinformation. If a defect is detected from this information, the area ofthe disc in which the defect exists and the following area containingdata may be regarded as unavailable, i.e., the two areas are designatedas a defective area, and the final temporary defect managementinformation and temporary defect information may be again recorded afterthe defective area.

INDUSTRIAL APPLICABILITY

As is described above, the present invention provides a disc defectmanagement method that is applicable to write once discs and which issuitable to record different types of data so as to enable moreappropriate real-time data reproduction of data. Further, according tothe present invention, a temporary defect information area is allottedto the data area of a disc, which stores defect information withoutreducing the recording capacity of the disc. During the finalization ofa disc, only the most recently recorded defect information is read fromthe temporary defect information area and recorded in a defectmanagement area (DMA) so as to enable efficient use of the DMA whoserecording capacity is limited. Meanwhile, recording user data on even awrite once disc while performing defect management is possible. Thus,more stable backup operations may be performed without interruptions.

Although a few embodiments of the present invention have been shown anddescribed, it would be appreciated by those skilled in the art thatchanges may be made in these embodiments without departing from theprinciples and spirit of the invention, the scope of which is defined inthe claims and their equivalents.

1. A method of managing defects in a disc, comprising: (a) recordingdata in predetermined units of data; (b) verifying the recorded data todetect an area of the disc in which a defect exists; (c) designating anarea from the defective area to the following area containing data as adefective area or designating only the defective area as the defectivearea; (d) recording information regarding the designated defective areaas temporary defect information in a data area of the disc; and (e)recording information, which is used to manage the temporary defectinformation, in a temporary defect management information area.
 2. Themethod of claim 1, further comprising; (f) repeating operations (a)through (e) before finalizing of the disc, wherein previously recordedinformation is recorded with the temporary defect information during the(d) operation; and (g) recording information, which is most recentlyrecorded in the temporary defect information area and the temporarydefect management information area in a defect management area duringthe finalizing of the disc.
 3. The method of claim 1, wherein during the(c) operation, the area from the area having the defect to the followingarea containing data is designated as a the defective area or only thearea having the defect is designated as the defective area, depending onthe type of the recorded data.
 4. The method of claim 3, wherein duringthe (c) operation, only the defective area is designated as thedefective area when the recorded data is AV data, and the area from thedefective area to the following area containing data is designated asthe defective area when the recorded data is control data.
 5. A methodof managing defects in a disc, comprising: (a) recording data inpredetermined units of data; (b) verifying the recorded data to detectan area of the disc in which a defect exists; (c) designating an areafrom the defective area to the following area containing data as adefective area as a defective area, or designating only the defectivearea as the defective area; (d) storing information regarding thedesignated defective area as first temporary defect information inmemory; (e) repeating operations (a) through (d) before a recordingoperation is expected to end; (f) reading the temporary defectinformation from the memory and recording the temporary defectinformation in a temporary defect information area of the data area soas to correspond to the recording operation, when the recordingoperation is expected to end; and (g) recording information, which isused to manage the information recorded in the temporary defectinformation area in the (f) operation, in a temporary defect managementinformation area.
 6. The method of claim 5, wherein during the (f)operation, information to designate the temporary defect informationarea is further recorded in the temporary defect information area. 7.The method of claim 6, further comprising: (h) repeating operations (a)through (e before finalizing of the disc, wherein previously recordedinformation is recorded with the temporary defect information during the(f) operation in the temporary defect information area; and (i)recording information, which is most recently recorded in the temporarydefect information area and the temporary defect management informationarea, in a defect management area.
 8. The method of claim 5, whereinduring the (c) operation, the area from the defective area to thefollowing area containing data is designated as the defective area, oronly the defective area is designated as the defective area, dependingon the type of the recorded data.
 9. The method of claim 8, whereinduring the (c) operation, only the defective area is designated as adefective area when the recorded data is AV data, and the area from thedefective area to the following area containing data is designated asthe defective area when the recorded data is control data.
 10. Arecording apparatus comprising; a recording/reading unit that recordsdata on or reads data from a disc; and a controller that verifies thedata recorded on the disc using the recording/reading unit so as todetect an area of the disc in which a defect exists, designates an areafrom the defective area to the following area containing data as adefective area or designates only the defective area as the defectivearea, creates information regarding the designated defective area,provides the created information to the recording/reading unit, controlsthe recording/reading unit to record the created information astemporary defect information in a data area of the disc, createsmanagement information for managing the temporary defect information,provides the management information to the recording/reading unit, andcontrols the recording/reading unit to record the management informationin a temporary defect management area.
 11. The recording apparatus ofclaim 10, wherein the controller controls the recording/reading unit tofurther record the previously recorded information with the information,and controls the recording/reading unit to record information, which ismost recently recorded in the temporary defect information area and thetemporary defect management information area in a defect management areaduring finalizing of the disc.
 12. The recording apparatus of claim 10,wherein the controller designates the area from the defective area tothe following area containing data as the defective area, or designatesonly the area having the defect as the defective area, depending on thetype of the recorded data.
 13. The recording apparatus of claim 12,wherein the controller designates only the area having the defect as thedefective area when the recorded data is AV data, and designates thearea from the area having the defect to the following area containingdata as the defective area when the recorded data is control data.
 14. Arecording apparatus comprising: memory; a recording/reading unit thatrecords data on a disc in predetermined units of data and reads therecorded data from the disc; and a controller that verifies the datarecorded on the disc using the recording/reading unit so as to defect anarea of the disc in which a defect exists; designates an area from thedefective area to the following area containing data as a defective areaor designates only the defective area as the defective area; storesinformation regarding the designated defective area as first temporarydefect information in the memory; repeats the verifying of the data, thedesignating of the defective area, and the storing of informationregarding the designated defective area before a recording operation isexpected to end; reads the temporary defect information from the memorywhen the recording operation is expected to end; provides the readtemporary defect information to the recording/reading unit; controls therecording/reading unit to record the temporary defect information in atemporary defect information area of the data area in a mannercorresponding to the recording operation; creates management informationfor managing the temporary defect information area; provides themanagement information to the recording/reading unit; and controls therecording/reading unit to record the management information in atemporary defect management information area.
 15. The recordingapparatus of claim 14, wherein the controller creates information forthe temporary defect information area, provides the created informationto the recording/reading unit, and controls the recording/reading unitto further record the created information in the temporary defectinformation area.
 16. The recording apparatus of claim 14, wherein thecontroller controls the recording/reading unit to further record thepreviously recorded information with the information; reads information,which is most recently recorded in the temporary defect information areaand the temporary defect management information area, during thefinalizing of the disc; and controls the recording/reading unit torecord the most recently recorded information in the defect managementarea again.
 17. The recording apparatus of claim 14, wherein thecontroller designates the area from the defective area to the followingarea containing data as the defective area or designates only thedefective area as the defective area, depending on the type of therecorded data.
 18. The recording apparatus of claim 17, wherein thecontroller designates only the defective area as the defective area whenthe recorded data is AV data, and designates the area from the defectivearea to the following area containing data as the defective area whenthe recorded data is control data.
 19. A disc having defect managementstructures, comprising: a data area in which data and informationregarding designated defective area are recorded, wherein an area fromthe defective area to the following area containing data is designatedas the defective area or only the defective area is designated as thedefective area.
 20. The disc of claim 19, wherein the area from the areahaving the defect to the following area containing data is designated asthe defective area or only the area having the defect is designated asthe defective area, depending on the type of the recorded data.
 21. Thedisc of claim 20, wherein only the defective area is designated as thedefective area when the recorded data is AV data, and the area from thedefective area to the following area containing data is designated asthe defective area when the recorded data is control data.